urinary systems and components 1

Question 1

what are the components are the urinary system?

Answer 1

2 kidneys, 2 ureters, a urinary bladder and urethra.

Question 2

what is nephrology?

Answer 2

scientific study of anatomy, physiology and pathology of kidney

Question 3

what is urology ?

Answer 3

a branch of medicine dealing with male and female urinary systems and male reproductive system.

Question 4

what are the 8 functions of kidney?

Answer 4

1) regulation of blood ion composition (Na +, K+, Ca2+, [HPO4]2-.
2) maintenance of blood osmolarity.( regulating loss of water and solutes in urine, maintains 290mOsm/litre)
3) regulation of blood volume ( by conserving or eliminating water).
4) regulation of blood pressure.
5) regulation of blood pH
6) release of hormones (calcitriol and erythropoietin)
7) regulation of blood glucose level
8) secretion of waste & foreign substances.

Question 5

How do kidneys regulate blood pressure ?

Answer 5

• Adjusting blood volume (= adjusting blood pressure)
• Renin secretion (increases vasoconstriction & blood volume = increased blood pressure)
• adjusts renal resistance (increases renal resistance = increased blood pressure)

Question 6

what waste and foreign substances does the kidneys secrete through urine?

Answer 6

-Ammonia and urea (from AA)
- bilirubin (from catabolism of Hb)
- creatinine (from breakdown of creatinine phosphate in muscles)
- uric acid (from catabolism of nucleic acids
- drugs and environmental toxins.

Question 7

Where are the kidneys found in the body?

Answer 7

Paired above waist at concave side, all blood & lymphatic vessels, nerves and ureter enter/leave by the renal hilum.

Question 8

what are the 3 layers of tissue surrounding the kidneys?

Answer 8

renal capsule, adipose capsule, renal fascia.

Question 9

describe the renal cortex in the kidneys.

Answer 9

outer, smooth, reddish.

Question 10

what are the portions that extend between the renal pyramids called?

Answer 10

renal columns.

Question 11

Describe the renal medulla in the kidneys.

Answer 11

Inner, reddish/brown. consists of 8-18 cone shaped renal pyramids.

Question 12

where are the renal papilla found ?

Answer 12

the part of the renal pyramid that points to the centre.

Question 13

what is the renal parenchyma?

Answer 13

the functional part of the kidney. composed of renal cortex and renal pyramids

Question 14

Describe nephrons in the kidneys.

Answer 14

Functional unit of the kidney, within parenchyma, 1 million microscopic units.

Question 15

where is urine formed?

Answer 15

in the nephron.

Question 16

Explain how urine travels.

Answer 16

Urine formed in nephron – papillary ducts – minor or major – renal pelvis – ureter – urinary bladder

Question 17

explain the renal corpuscle .

Answer 17

It filters the plasma,
- glomerulus , mass of capillary loops
- Bowmans capsule - glomerular capsule surrounds glomerulus.

Question 18

explain renal tubules

Answer 18

into which filtered fluid passes-
1 - proximal convoluted - attached to Bowman’s capsule.
2) loop of henle - descending, hairpin, ascending
3) distal convoluted tubule.

Question 19

do kidneys contain abundant supply of blood vessels?

Answer 19

yes, they remove waste from blood and regulate its volume and composition.

Question 20

what % of kidneys take up body mass?

Answer 20

Less than 0.5 %, but recieve 20-25% cardiac output via L & R renal arteries.

Question 21

What is an adults renal blood flow per minute?

Answer 21

1.2 litres per minute.

Question 22

explain the path of blood Flow through the kidneys.

Answer 22

Large arteries to small, small to large veins.

Question 23

Explain the composition of glomerular (bowmans) capsule.

Answer 23

• Outer parietal layer wall of simple squamous epithelium.
• inner visceral layer of specialised simple squamous epithelial cells = podocytes.

Question 24

what do podocytes (inner visceral cells) do?

Answer 24

podocytes - wrap around the glomerular capillaries.

Question 25

what 2 things make up the filtration membrane?

Answer 25

podocytes and fenestrated capillaries, it is 0.1 mm thick.

Question 26

what passes from blood to capsular space if molecule is less than 6nm? what stays in blood?

Answer 26

H2O, Glucose, Vitamins, AA, Small plasma proteins, urea, ammonia, ions.
Stays in blood - albumen 7.1nm, plasma proteins, platelets, rbc , wbc

Question 27

what does prominent brush border of microvilli in proximal convoluted tubule cells do?

Answer 27

increases surface area for reabsorption and secretion.

Question 27

Last portion of distal collecting duct has 2 different cells, what are they?

Answer 27

Mainly - principal cells(receptors for ADH and aldosterone)
fewer - intercalated cells ( apical microvilli and many mitochondria , play a role in haemostasis of blood pH.

Drain to large papillary ducts. lined by simple columnar epithelial cells.